U.S. patent application number 13/186427 was filed with the patent office on 2012-01-19 for medical devices with detachable pivotable jaws.
This patent application is currently assigned to COOK MEDICAL TECHNOLOGIES LLC. Invention is credited to Andres F. Aguirre, Michelle D. Martinez, Vihar C. Surti.
Application Number | 20120016391 13/186427 |
Document ID | / |
Family ID | 46551931 |
Filed Date | 2012-01-19 |
United States Patent
Application |
20120016391 |
Kind Code |
A1 |
Aguirre; Andres F. ; et
al. |
January 19, 2012 |
MEDICAL DEVICES WITH DETACHABLE PIVOTABLE JAWS
Abstract
Medical systems, devices and methods are provided for engaging
tissue, e.g. for clipping tissue, closing a perforation or
performing hemostasis. Generally, the medical system including a
housing, first and second jaws rotatable relative to the housing, a
driver, and an elongate drive wire. The elongate drive wire may be
disconnected from the driver, first and second jaws, and the
housing, which are left in vivo engaged with the tissue.
Inventors: |
Aguirre; Andres F.;
(Chicago, IL) ; Surti; Vihar C.; (Winston-Salem,
NC) ; Martinez; Michelle D.; (Winston-Salem,
NC) |
Assignee: |
COOK MEDICAL TECHNOLOGIES
LLC
Bloomington
IN
|
Family ID: |
46551931 |
Appl. No.: |
13/186427 |
Filed: |
July 19, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12971873 |
Dec 17, 2010 |
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13186427 |
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61289297 |
Dec 22, 2009 |
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61391881 |
Oct 11, 2010 |
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Current U.S.
Class: |
606/151 |
Current CPC
Class: |
A61B 17/08 20130101;
A61B 2017/2925 20130101; A61B 2017/2936 20130101; A61B 2017/2902
20130101; A61B 2017/2937 20130101; A61B 2017/2946 20130101; A61B
2017/2943 20130101; A61B 17/122 20130101; A61B 2017/2944 20130101;
A61B 2017/2931 20130101; A61B 17/1285 20130101; A61B 2017/294
20130101; A61B 2017/00473 20130101; A61B 2017/12004 20130101; A61B
17/10 20130101 |
Class at
Publication: |
606/151 |
International
Class: |
A61B 17/00 20060101
A61B017/00 |
Claims
1. A medical device for engaging tissue, the medical device
comprising: a housing defining an internal passageway and a
longitudinal axis extending between proximal and distal ends of the
housing, the housing defining a driver guide surface along the
internal passageway; a first jaw rotatable relative to the housing,
the first jaw having proximal and distal ends; a second jaw
rotatable relative to the housing, the second jaw having proximal
and distal ends; an elongated drive wire; and a driver having a
proximal portion engaged with the drive wire and a distal portion
engaged with the proximal ends of the first and second jaws,
longitudinal movement of the driver rotating the first and second
jaws relative to the housing, the driver including an intermediate
portion positioned between the proximal and distal portions, the
intermediate portion including a frame and a locking leg connected
to the frame, the frame defining an intermediate space, the frame
being deformable such that a predetermined longitudinal force
differential between the proximal portion and distal portion of the
driver causes the frame to deform and the locking leg to move away
from the longitudinal axis into a locking position for engaging the
driver guide surface.
2. The medical device of claim 1, wherein a length of the driver
increases upon deformation of the frame.
3. The medical device of claim 1, wherein the frame circumscribes
the intermediate space.
4. The medical device of claim 1, wherein the intermediate space
has a general C-shape prior to deformation of the frame, and a
generally rectangular shape after deformation of the frame.
5. The medical device of claim 1, wherein a longitudinal distance
of the intermediate space increases after deformation.
6. The medical device of claim 1, wherein the locking leg rotates
away from the longitudinal axis
7. The medical device of claim 1, wherein the frame plastically
deforms.
8. The medical device of claim 1, wherein the frame includes a
proximal member extending laterally, a distal member extending
laterally, and a pair of side members connecting the proximal and
distal members.
9. The medical device of claim 8, wherein the locking leg is
connected to the distal member and one of the side members.
10. The medical device of claim 9, wherein the distal member
defines a deformable area adjacent the locking leg.
11. The medical device of claim 9, wherein the distal member,
locking leg, and the one side member together deform under the
predetermined longitudinal force differential to move the locking
leg away from the longitudinal axis.
12. The medical device of claim 9, further comprising a second
locking leg connected to the distal member and one of the side
members.
13. The medical device of claim 1, wherein the locking leg has a
general V-shape and defines a portion of the intermediate
space.
14. The medical device of claim 1, further comprising a neck
interconnecting the proximal portion of the driver and the
intermediate portion of the driver.
15. The medical device of claim 14, wherein the neck is breakable
upon a second predetermined longitudinal force differential between
the proximal portion and the intermediate portion of the driver
16. The medical device of claim 15, wherein the second
predetermined longitudinal force differential is greater than the
predetermined longitudinal force differential that deforms the
frame.
17. The medical device of claim 1, wherein the first jaw has a
proximal end slidably and pivotally connected to the housing, the
first jaw slidably received within the internal passageway for
longitudinal movement between an extended position and a retracted
position, and wherein the second jaw has a proximal end slidably
and pivotally connected to the housing, the second jaw slidably
received within the internal passageway for longitudinal movement
between an extended position and a retracted position;
18. The medical device of claim 17, wherein the proximal ends of
the first and second jaws include gears having teeth, and wherein
the driver includes corresponding teeth that mesh with the teeth of
the jaws.
19. The medical device of claim 17, wherein the proximal ends of
the first and second jaws are formed as pinions, and wherein the
driver is formed as a rack, wherein longitudinal movement of the
driver and rack rotates the pinions of the first and second jaws in
their extended positions.
20. The medical system of claim 1, wherein the driver guide surface
includes a proximal portion and distal portion and a shoulder at
the transition between of the proximal and distal portions, the
shoulder facing proximally, and wherein the locking leg is
positioned to engage the shoulder to limit longitudinal movement of
the driver after the locking leg has been moved laterally outwardly
by deformation of the frame of the driver.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent
application Ser. No. 12/971,873 filed on Dec. 17, 2010, which
claims the benefit of U.S. Provisional Application Ser. No.
61/289,297 filed on Dec. 22, 2009, entitled "MEDICAL DEVICES WITH
DETACHABLE PIVOTABLE JAWS," and further claims the benefit of the
filing date under 35 U.S.C. .sctn.119(e) of Provisional U.S. Patent
Application Ser. No. 61/391,881 filed Oct. 11, 2010. All of the
foregoing applications are hereby incorporated by reference.
BACKGROUND
[0002] Conventionally, a clip may be introduced into a body cavity
through an endoscope to grasp living tissue of a body cavity for
hemostasis, marking, and/or ligating. Such clips are often known as
surgical clips, endoscopic clips, hemostasis clips and vascular
clips. In addition, clips are now being used in a number of
applications related to gastrointestinal bleeding such as peptic
ulcers, Mallory-Weiss tears, Dieulafoy's lesions, angiomas,
post-papillotomy bleeding, and small varices with active bleeding.
Clips have also been attempted for use in closing perforations in
the stomach
[0003] Gastrointestinal bleeding is a somewhat common and serious
condition that is often fatal if left untreated. This problem has
prompted the development of a number of endoscopic therapeutic
approaches to achieve hemostasis such as the injection of
sclerosing agents and contact thermo-coagulation techniques.
Although such approaches are often effective, bleeding continues
for many patients and corrective surgery therefore becomes
necessary. Because surgery is an invasive technique that is
associated with a high morbidity rate and many other undesirable
side effects, there exists a need for highly effective, less
invasive procedures.
[0004] Mechanical hemostatic devices such as clips have been used
in various parts of the body, including gastrointestinal
applications. One of the problems associated with conventional
hemostatic devices and clips, however, is that many devices are not
strong enough to cause permanent hemostasis. Further, clips have
also been attempted for use in closing perforations in the stomach
or gastrointestinal structures, but unfortunately traditional clips
suffer from difficult placement and the capability to grasp a
limited amount of tissue, potentially resulting in incomplete
closure.
BRIEF SUMMARY
[0005] The invention may include any of the following aspects in
various combinations and may also include any other aspect
described below in the written description or in the attached
drawings.
[0006] In a first aspect, a medical device is provided for engaging
tissue, the medical device including a housing, first and second
jaws, an elongated drive wire, and a driver. The housing defines an
internal passageway and a longitudinal axis extending between
proximal and distal ends of the housing. The housing also defines a
driver guide surface along the internal passageway. The first and
second jaws are rotatable relative to the housing, and each have
proximal and distal ends. The driver has a proximal portion engaged
with the drive wire and a distal portion engaged with the proximal
ends of the first and second jaws. Longitudinal movement of the
driver rotates the first and second jaws relative to the housing.
The driver also includes an intermediate portion positioned between
the proximal and distal portions. The intermediate portion includes
a frame and a locking leg connected to the frame, the frame
defining an intermediate space. The frame is deformable such that a
predetermined longitudinal force differential between the proximal
portion and distal portion of the driver causes the frame to deform
and the locking leg to move away from the longitudinal axis into a
locking position for engaging the driver guide surface.
[0007] According to more detailed aspects, the length of the driver
increases upon deformation of the frame. The frame circumscribes
the intermediate space, and the intermediate space has a general
C-shape prior to deformation of the frame, and a generally
rectangular shape after deformation of the frame. The longitudinal
distance of the intermediate space increases after deformation, and
the locking leg preferably rotates away from the longitudinal axis.
The driver may also include a neck interconnecting the proximal
portion of the driver and the intermediate portion of the driver.
In one variation, the neck is breakable upon a second predetermined
longitudinal force differential between the proximal portion and
the intermediate portion of the driver. The second predetermined
longitudinal force differential is greater than the predetermined
longitudinal force differential that deforms the frame. In another
variation, the neck is not breakable, but rather the proximal
portion and its socket deforms to allow the drive wire and related
structures to be released, leaving the clip in vivo and locked to
the tissue.
[0008] According to still further detailed aspects, the frame
preferably includes a proximal member extending laterally, a distal
member extending laterally, and a pair of side members connecting
the proximal and distal members. The locking leg is connected to
the distal member and one of the side members, and the distal
member defines a deformable area adjacent the locking leg. In some
constructions, the distal member, locking leg, and the one side
member together deform under the predetermined longitudinal force
differential to move the locking leg away from the longitudinal
axis. The locking leg may have a general V-shape and define a
portion of the intermediate space. The housing's driver guide
surface includes a proximal portion and distal portion and a
shoulder at the transition between of the proximal and distal
portions. The shoulder faces proximally, and the locking leg is
positioned to engage the shoulder to limit longitudinal movement of
the driver after the locking leg has been moved laterally outwardly
by deformation of the frame of the driver.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings incorporated in and forming a part
of the specification illustrate several aspects of the present
invention, and together with the description serve to explain the
principles of the invention. In the drawings:
[0010] FIG. 1 is a top view of a medical system having a medical
device for engaging tissue, constructed in accordance with the
teachings of the present invention;
[0011] FIG. 2 is a top view similar to FIG. 1, but showing the
outer structures in dotted lines and the interior sections in solid
lines and partial cross section;
[0012] FIG. 3 is a side view of the medical system and device
depicted in FIG. 1;
[0013] FIG. 4 is a side view similar to FIG. 3, but showing the
outer structures in dotted lines and the interior structures in
solid lines and partial cross section
[0014] FIG. 5 is a side view of a medical device that is part of
the medical system depicted in FIGS. 1-4;
[0015] FIG. 6 is a front view of a housing forming a portion of the
medical system and device depicted in FIGS. 1-5;
[0016] FIG. 7 is a perspective view of the housing depicted in FIG.
6;
[0017] FIGS. 8-12 are side views showing operation of the medical
system and device depicted in FIGS. 1-5;
[0018] FIGS. 13 and 14 are top views, partially in cross-section,
depicting operation of the medical system and device depicted in
FIGS. 1-4;
[0019] FIGS. 15 and 16 are cross-sectional views showing operation
of the medical system and device depicted in FIGS. 1-4.
[0020] FIGS. 17 and 18 are a perspective view of an alternate
embodiment of a grasping jaw forming a portion of the medical
system and device of FIG. 1;
[0021] FIG. 19 is a plan view of an alternate embodiment of a
driver forming a portion of the medical system and device of FIG.
1;
[0022] FIG. 20 is a perspective view of the driver of FIG. 19 shown
attached to a drive wire;
[0023] FIG. 21 is a side view of FIG. 20;
[0024] FIG. 22a is a plan view of an alternate embodiment of the
medical device of FIG. 1, and FIG. 22b is a plan view of the driver
of FIG. 19 shown attached to a strip and forming a portion of the
medical device of FIG. 22a;
[0025] FIG. 23 is a plane view of another alternate embodiment of
the medical device depicted in FIG. 1;
[0026] FIGS. 24 and 25 are a perspective views showing operation of
the medical device depicted in FIG. 23;
[0027] FIGS. 26 and 27 are perspective and end views, respectively,
of another embodiment of a driver forming a portion of the medical
system and device depicted in FIG. 1;
[0028] FIG. 28 is a perspective view of the driver of FIGS. 25-26
shown attached to the jaws;
[0029] FIGS. 29 and 30 are plan views showing operation of the
driver and jaws depicted in FIG. 28;
[0030] FIGS. 31 and 32 are cross-sectional views of another
embodiment of the medical system and device depicted in FIG. 1;
[0031] FIG. 33 is a perspective view of the medical system and
device depicted in FIGS. 31 and 32;
[0032] FIGS. 34-37 are plan views showing operation of another
alternate embodiment of a driver forming a portion of the medical
system and device of FIG. 1; and
[0033] FIG. 38 is a plan view of yet another alternate embodiment
of a driver forming a portion of the medical system and device of
FIG. 1.
DETAILED DESCRIPTION
[0034] The terms "proximal" and "distal" as used herein are
intended to have a reference point relative to the user.
Specifically, throughout the specification, the terms "distal" and
"distally" shall denote a position, direction, or orientation that
is generally away from the user, and the terms "proximal" and
"proximally" shall denote a position, direction, or orientation
that is generally towards the user.
[0035] An exemplary medical system 20 having a medical device 40
for engaging tissue T (FIG. 11) is shown in FIGS. 1 through 4. The
medical system 20 and device 40 are generally sized and structured
for operation through the working channel of an endoscope (not
shown) or other scope, although the system 20 and device 40 may
also be used alone or in conjunction with other elongate devices
such as catheters, fiber-optic visualization systems, needles and
the like. Generally, the medical system 20 includes a drive wire 22
slidably housed within the distal end 23 of an elongated catheter
24 for selective connection to, and operation of, the medical
device 40. As will be described in further detail herein, the
medical device 40 generally includes a housing 42 having a first
jaw 44 and a second jaw 46 pivotally connected thereto for engaging
the tissue T. Generally, the jaws 44, 46 have been shown as forming
grasping forceps, although the jaws are intended to be used to clip
tissue, e.g. to close an opening or for hemostasis. Accordingly, it
will be recognized that the shape and structure of the jaws may
take many forms and serve many purposes and functions, all in
accordance with the teachings of the present invention.
[0036] In the medical system 20, the drive wire 22 slidably extends
through the catheter 24. Although the term "wire" is used to refer
to the drive wire 22, it will be recognized that any elongate
control member capable of transmitting longitudinal force over a
distance (such as is required in typical endoscopic, laparoscopic
and similar procedures) may be used, and this includes plastic rods
or tubes, single filament or multi-filament wires, metal rods and
the like. The drive wire 22 should also be capable of properly
transmitting a rotational/torsional force from the proximal end to
the distal end to rotate the medical device 40 and jaws 44, 46, and
thus it is currently preferred that the drive wire 22 is formed
from nitinol (e.g. a nitinol wire) or other superelastic alloy. A
connection block 26 is slidably fitted within the distal end 23 of
the catheter 24 and defines a bore 28 therethrough which slidably
receives the drive wire 22. The exterior of the connection block 26
includes a recessed portion 27, and two pins 30 (e.g., formed from
stainless steel wire) are connected to the catheter 24 and
positioned within the recessed portion 27 to limit the longitudinal
movement of the connection block 26.
[0037] A distal end of the drive wire 22 defines a distal head 32
that is sized larger than the drive wire 22, and likewise larger
than the bore 28 in the connection block 26. As will be described
later herein, the distal head 32 is used to slide the connection
block 26 within the catheter 24 to disconnect the medical device 40
from the medical system 20. As also seen in FIGS. 1-4, the housing
42 of the medical device 40 is a tubular member defining an
interior space 43. A proximal end of the housing 42 frictionally
receives a distal end of the connection block 26 within the
interior space 43 for selective connection therewith.
[0038] The internal passageway 43 of the housing 42 also receives
the first and second jaws 44, 46 and a driver 48 which is used to
interconnect the drive wire 22 to the jaws 44, 46. As best seen in
FIGS. 1, 2 and 5, the driver 48 has a proximal portion which
defines a socket 50 sized to receive enlarged distal head 32 of the
drive wire 22. At the proximal entrance of the socket 50, two
deflectable locking tabs 52 are formed which rotate relative to the
remainder of the driver 48 to increase or decrease the size of the
socket 50. The locking tabs 52 may be separately formed and
pivotally attached to the driver 48, or may be integrally formed
with the driver 48 and formed of a resilient material which flexes
to permit rotation of the locking tabs 52 radially inwardly and
radially outwardly. A distal portion of the driver 48 defines a
rack 54 for engaging and operating the jaws 44, 46. In the depicted
embodiment, the rack 54 includes a central spine 56 having teeth 58
projecting away from the central spine 56 and on opposite sides of
the spine 56. One set of teeth 58 on one side of the spine 56
generally operate the first jaw 44 while the other set of teeth 58
on the other side of the spine 56 operate the second jaw 46. It
will be recognized that the rack 54 may include a single set of
teeth or other geared structures that interface with the jaws 44,
46.
[0039] As best seen in FIG. 5, the first and second jaws 44, 46
include distal ends 60, 62 that are structured to grasp and engage
tissue, generally they have a talon shape as disclosed in
61/141,934 filed Dec. 31, 2008, the disclosure of which is
incorporated herein by reference in its entirety. The proximal ends
64, 66 of the first and second jaws 44, 46 each include a pinion
gear 68, 70 having a series of teeth. The teeth of the pinion 68,
70 mesh with the teeth of the rack 54 of the driver 48 such that
longitudinal translation of the driver 48 induces rotation in the
first and second jaws 44, 46 relative to one another. Generally,
distal translation of the driver 48 causes the first and second
jaws 44, 46 to rotate outwardly away from each other, while
proximal retraction of the driver 48 causes the first and second
jaws 44, 46 to rotate inwardly toward one another. Pins 80 are
fitted through each the proximal ends of the jaws 44, 46, to
pivotally connect the jaws to the housing 42. Other structures for
forming a pivotal connection may be used, and preferably the
pivotal connection is centrally arranged relative to the pinions
68, 70.
[0040] In addition to the jaws 44, 46 being pivotally attached to
the housing 42, the first and second jaws 44, 46 are also slidably
attached to the housing 42. As best seen in FIGS. 6 and 7 (and in
conjunction with FIGS. 1-4) the housing 42 defines a first guide
surface 82 for the first jaw 44, and a second guide surface 84 for
the second jaw 46. As seen in FIG. 3, the first and second guide
surfaces 82, 84 are formed by elongated slots 82a, 82b, 84a, 84b
formed in opposing sides of the housing 42 which leaves a thickness
of the housing 42 exposed to serve as the guide surface. The slots
82a, 82b are aligned to receive the connecting pin 80 of the first
jaw 44, and likewise the slots 84a, 84b are aligned to receive the
connecting pin 80 of the second jaw 46. The ends of the slots, for
example distal ends 92, 94 shown in FIG. 7, serve to restrict the
longitudinal movement of the jaws 44, 46 relative to the housing
42. The proximal ends 64, 66 of the jaws 44, 46 include apertures
72, 74 which receive the pins 80 (FIGS. 1, 2 and 3) that are used
to slidably and pivotally connect the first and second jaws 44, 46
to the housing 42.
[0041] It can also be seen in FIGS. 6 and 7 that the housing 42
defines a third guide surface 86 which guides the longitudinal
movement of the driver 48 within the housing 42. The guide surface
86 in the depicted embodiment includes a left guide surface 86a and
a right guide surface 86b formed as C-shaped channels. As shown in
FIG. 7, the third guide surface 86 transitions from a smaller
proximal width to a larger distal width to define a shoulder 88 at
the transition, which will be further described hereinbelow with
reference to FIGS. 13 and 14.
[0042] As also shown in FIG. 6, the internal passageway 43 of the
housing 42 extends through the distal end of the housing, and
through which the first and second jaws 44, 46 can extend.
Additionally, as shown in FIGS. 1 and 2, the housing 42 defines
opposing slots 45 which are sized to permit the first and second
jaws 44, 46 to pass therethrough when they rotate radially
outwardly. Accordingly, it is also clear from FIGS. 1 and 2 that
the housing 42 serves to block rotation of the first and second
jaws 44, 46 when they are entirely or partially contained within
the internal passageway 43 of the housing 42. Suitable plastics for
forming the housing include, but are not limited to,
polytetrafluorethylene (PTFE), expanded polytetrafluorethylene
(EPTFE), polyethylene ether keytone (PEEK), polyvinylchloride
(PVC), polycarbonate (PC), polyamide, polyimide, polyurethane,
polyethylene (high, medium or low density), and suitable metals
include stainless steel, nitinol and similar medical grade metals
and alloys.
[0043] Operation of the medical device 40 will now be described
with reference to FIGS. 8-12. As shown in FIG. 8, the first and
second jaws 44, 46 are shown in a retracted position where they are
substantially contained within the housing 42. Depending on the
application, the distal ends 60, 62 of the jaws 44, 46 may slightly
project from the distal end of the housing 42 in their retracted
positions, or they may be entirely positioned within the housing
42. When the drive wire 22 is translated distally (to the right on
the page in FIG. 8) the distal head 32 engages the driver 48, the
driver 48 and jaws 44, 46 slide distally through the housing 42.
The driver 48 and jaws 44, 46 slide longitudinally before they
rotate (even though the rack 54 of the driver 48 is meshed with the
pinions 68, 70 at the proximal ends 64, 60 of the jaws 44, 46)
since the resistance to longitudinal movement is less than the
force required to rotate the jaws 44, 46 (alternatively, the
housing 42 can block rotation of the jaws 44, 46 when they are
within the housing 42). As previously mentioned, this longitudinal
movement is guided by the first and second guide surfaces 82, 84
which receive the pins 80 that slidably and pivotally connect the
jaws 44, 46 to the housing 42.
[0044] As shown in FIG. 9, the first and second jaws 44, 46 have an
extended position where the jaws substantially project from a
distal end of the housing 42, and their proximal ends 64, 66 are
positioned adjacent the distal end of the housing 42. Accordingly,
it will be seen that further distal advancement of drive wire 22,
and hence the driver 48, causes the pinion 68 to rotate over the
teeth 58 of the rack 54. As best seen in FIG. 10, the first and
second jaws 44, 46 rotate radially outwardly from each other into a
tissue receiving position. Notably, due to the presence of slots 45
at the distal end of the housing 42, the jaws 44, 46 are permitted
to rotate a full 90.degree., thus forming at least a 180.degree.
between them. It will be recognized that through the sizing of the
slots 45 and the construction of the rack 54 and pinions 68, 70,
the first and second jaws 44, 46 may rotate even further away from
each other.
[0045] In the tissue receiving configuration shown in FIG. 10, the
medical device 40 and its jaws 44, 46 may be positioned adjacent
tissue T. As shown in FIG. 11, the tissue T may be placed between
the first and second jaws 44, 46 and the jaws 44, 46 rotated back
towards their position shown in FIG. 9. The tissue T has been shown
as a single layer, although multiple layers may be clipped between
the jaws 44, 46. Generally, proximal retraction of the drive wire
22 and the driver 48 again causes rotation of the first and second
jaws 44, 46 to grasp the tissue T therebetween. As shown in FIG.
12, further proximal retraction of the drive wire 22 and driver 48
will cause the jaws 44, 46 to move longitudinally in a proximal
direction (to the left on the page in FIG. 12).
[0046] In order for the medical device 40 to serve as a clip and
maintain its grasp on the tissue T, or to maintain the clipping of
two layers of tissue against each other, the jaws 44, 46 may be
locked in position and the drive wire 22 of the medical system 20
disconnected from the medical device 40. As shown in FIG. 13, the
third guide surface 86 (which guides the driver 48) includes a
proximal portion 86p and a distal portion 86d. The proximal portion
86p of the third guide surface 86 has a width (measured up and down
on the page in FIG. 13) that is greater than a width of the distal
portion 86d of the third guide 86. As previously discussed, the
third guide surface 86 is formed by opposing surfaces or C-shaped
channels 86a, 86b of the housing 42. The transition between the
proximal portion 86p and distal portion 86d defines a shoulder 88,
and namely two shoulders 88a, 88b on opposing sides of the housing
42. The shoulders 88a, 88b are sized and positioned to engage the
locking tabs 52 located on the driver 48.
[0047] As shown in FIG. 13, when the driver 48 is located within
the distal portion 86d of the third guide surface 86, the locking
tabs 52 are forced radially inwardly into firm frictional
engagement with the drive wire 22. Stated another way, the socket
50 formed by the driver 48 to receive the distal head 32 has an
entrance which is narrowed by the inward deflection of the locking
tabs 52. Preferably, the locking tabs 52 plastically deform rather
than elastically deform, and the tabs 52 may be bent inwardly
around the distal head 32 during initial assembly of the device,
and thus sized for the distal portion 86d of the third guide
surface 86. In this state depicted in FIG. 13, the drive wire 22 is
firmly engaged with the driver 48 and hence the first and second
jaws 44, 46.
[0048] When the drive wire 22 and driver 48 are retracted
proximally, for example upon grasping tissue as shown in FIG. 12,
the proximal end of the driver 48 is received within the proximal
portion 86p of the third guide surface 86 which has a larger width
that permits radially outward movement of the locking tabs 52.
Accordingly, in the state depicted in FIG. 14, the locking tabs 52
may be loosely and detachably connected to the distal head 32 of
the drive wire 22. That is, the proximal retraction of the jaws 44,
46 will be limited by either the tissue T engaging the distal end
of the housing 42, or the pins 80 will abut the proximal ends of
the slots 82a, 82b, 84a, 84b defining a first and second guide
surfaces 82, 84. As such, when proximal movement of the jaws 44, 46
and the driver 48 are thus limited, further proximal movement of
the drive wire 22 and its distal head 32 may be used to withdraw
the distal head 32 from the socket 50 of the driver 48. This
operation may also be used to further deflect the locking tabs 52
radially outwardly. An appropriate amount of distally directed
force on the drive wire 22 causes the distal head 32 to move
proximally through the locking tabs 52 and plastically deform them
radially outwardly. In the event the natural elasticity of the
tissue T tends to pull the jaws 44, 46 out from the housing towards
their extended position, the locking tabs 52, 54 will abut the
shoulders 88a, 88b of the third guide surface of the housing 42 to
prevent further distal movement of the jaws 44, 46.
[0049] Turning now to FIGS. 15 and 16, upon still further proximal
retraction of the drive wire 22 and distal head 32, the enlarged
distal head 32 will abut the connection block 26 which is slidably
fitted within the distal end 23 of the catheter 24. Sufficient
proximal force on the drive wire 22 will overcome the frictional
fit between the connection block 26 and the proximal end of the
housing 42, thus moving the connection block 26 proximally (to the
right on the page of FIGS. 15 and 16) to retract the connection
block 26 within the tubular connector 24, as shown in FIG. 16. The
catheter 24 can be used to provide a counterforce on the housing 42
while proximally retracting the drive wire 22 and connection block
26. Accordingly, the drive wire 22, catheter 24 and connection
block 26 may be fully disconnected from the medical device 40,
thereby leaving the first and second jaws 44, 46 and the housing 42
in a state having the tissue T clipped between the jaws 44, 46 and
retained in vivo. The connection block 26 is retained at the distal
end 24 of the catheter 24 via the pins 30, which are positioned
within the recessed area 27 to engage the proximal and distal ends
of the connection block 26 and limit its longitudinal movement.
[0050] The elongated catheter 24 (or other elongate tubular member
such as a sheath, tube, scope or the like), which slidably encases
the drive wire 22, extends proximally therealong to a proximal end
of the system 20, and has a length suitable for placing the device
40 at any desired location within the body, while the proximal ends
of drive wire 22 and catheter 24 are positioned outside of the body
for use by the medical professional. Control handles (not shown)
for controlling relative translation of the drive wire 22 and
catheter 24 are well known in the art, and may be employed at the
proximal end of the system 20.
[0051] Another embodiment and method of forming the grasping jaws
44, 46 are shown in FIGS. 17-18. The jaws of the prior embodiment
were generally machined, however the jaws 44, 46 may also be formed
by stamping. A flat piece of metal preferably of medical grade
stainless steel, is stamped into the shape 144 shown in FIG. 17.
The shape includes a slightly narrow distal end 160 which then can
be bent into the shape shown in FIG. 18 for grasping and engaging
tissue. The distal end 160 may also be stamped to include a
serrated edge, or other shapes or edge features depending upon the
application. The proximal end 164 generally includes two arms 166
which lead to gears 168. As shown in FIG. 18, the gears 168 are
grasped and then rotated about 90 degrees such that the gears 168
extend in a plane that is perpendicular to the plane of the sheet
144. The gears 168 also include a through-hole 172 for receiving a
guiding pin. It will also be recognized that the jaws 44, 46 in
this embodiment may also be formed of a single arm 166 and single
gear 168.
[0052] Another embodiment of a driver 148 and drive wire 122 are
shown in FIGS. 19-22. The driver 148 generally includes a socket
150 formed by two locking tabs 152. In this embodiment, a proximal
portion of the locking tabs define slanted shoulders 154 which
slope laterally outwardly for engagement with the third guide
surface 86 in the housing 42 as previously discussed. The locking
tabs 152 also include inner projections 153 which project laterally
inwardly and separate the socket 150 into a distal portion 150d and
a proximal portion 150p. The driver 148 again includes a central
spine 156 and opposing teeth 158. In this embodiment, the distal
end 166 of the driver 148 includes a pocket 168 defined by two
inwardly projecting flanges 170, as will be discussed further
herein. The two flanges 170 extend along a distal side of the
pocket 168, and leave a gap therebetween for access to the pocket
168.
[0053] As seen in FIGS. 20 and 21, this embodiment of the drive
wire 122 includes a distal head 132 which is formed by bending the
distal end of the drive wire 122 into a semi-circular shape as
shown, preferably spanning an arc of 180 degrees to 360 degrees.
Accordingly, it can be seen that the distal head 132 defines an
opening 133 that is sized to receive the inner projections 153 of
the locking tabs 152. As shown, the distal portion 150d of the
socket 150 receives the distal-most part of the curved distal head
132, while the proximal portion of the distal head 132 projects
through the proximal portion 150p of the socket 150 and proximally
away therefrom. As noted above, the locking tabs 152 here are
structured to be plastically deformed, and thus after formation and
connection to the drive wire 122 as shown in FIG. 19, the tabs 152
are bent radially inwardly to secure the projections 153 within the
opening 133 of the socket 132. In this state, the exterior
shoulders 154 of the locking tabs 152 are sized to fit within the
third guide surface 86, and more particularly the distal portion
86d of the third guide surface 86 without further deformation.
[0054] As shown in FIGS. 22a and 22b, another embodiment of the
medical device 140 may include the housing 142, grasping arms 144,
146 just as in the prior embodiment, but in this embodiment include
the alternate driver 148 and an additional biasing element, namely
a biasing strip 190. As best seen in FIG. 22b, the distal end 166
of the driver 148 receives the biasing strip 190 within the pocket
168. The flanges 170 are bent inwardly and proximally as shown to
firmly engage the metal strip 190 and fix it to the driver 148. The
biasing strip 190 is preferably a thin strip formed from a sheet of
resilient material, and more preferably a metal strip, e.g. formed
of stainless steel, nitinol or other super elastic alloy that is
biocompatible. Accordingly, it will be recognized that as the
driver 148 is moved proximally to cause the jaws 144, 146 to close,
the biasing strip 190 will be forced into a V-shape or U-shape, as
shown by the dotted lines in FIG. 22a. That is, the biasing strip
190 has a straight shape in its natural, unbiased, configuration,
and when bent into the V-shape it exerts a radially outward force
on the jaws 144, 146. This biasing force provides the jaws 144, 146
with smooth rotation and transition between the open and closed
positions. It will also be recognized that the biasing strip 190
could also have its original, unbiased position formed as a V-shape
or a U-shape, and be affixed to the jaws 144, 146 such that it
exerts a radially inward biasing force. The free ends 192 of the
metal strip 190 simply press against the jaws 44, 46, but are not
fixed or rigidly attached thereto.
[0055] Turning to FIG. 23, another embodiment of the medical device
240 is shown, again including a housing 242 and opposing jaws 244,
246 that are slidably attached thereto. The housing 242 again
includes first and second guides 282, 284 for guiding movement of
the jaws 244, 246. In this embodiment however, each jaw 244, 246
includes a biasing strip 290a, 290b, respectively. The distal ends
291 of the strips 290a, 290b are fixedly attached to the exterior
of the jaws 244, 246, preferably at their distal ends, and
preferably by way of an adhesive, soldering, welding, or other
known bonding techniques. As best seen in FIGS. 24 and 25, the
housing 240 includes two exterior channels 294 on opposite sides of
the housing 240 (one being shown in FIGS. 24 and 25) which are
sized to receive the resilient strips 290a, 290b such that they are
flush with the exterior surface of the housing in the
closed/retracted configuration. The proximal ends 293 of the strips
290a, 290b include a T-shaped formed by a base 295 and cross bar
296. The base 295 extends through a smaller slot 296 formed through
the housing 240. The slots 296 are coextensive with the channels
294. The cross bar 296 rides along the interior of the housing 240
and maintains the slidable connection between the strips 290 and
the housing 240. Accordingly, it can be seen that the proximal ends
293 of the strips 290a, 290b are slidably and pivotably attached to
the housing 240 via the channel 294 and its slot 296, allowing the
strips 290a, 290b to travel with the grasping jaws 44, 46 as shown
between their open and closed positions as shown in FIGS. 24 and
25.
[0056] Turning now to FIGS. 26-30, another embodiment of a driver
348 is shown. As best seen in FIGS. 26 and 27, the driver 348 again
includes a socket 350 formed by two locking tabs 352 which have
inner projections 353 and outer shoulders 354, and which divide the
socket 350 into a distal portion 353 and a proximal portion 350p.
Unlike the prior embodiments of the driver, in this embodiment the
distal portion defines a geared rack that has a Z-shape. Generally,
a central plate 356 replaces the central spine 56, 156 of the prior
embodiments, and the plate 356 extends in a plane that is parallel
to the longitudinal plane of the housing 342 (FIG. 29). The plane
of the central plate 356 is also perpendicular to a plane of the
proximal half of the driver 348 (i.e. that which includes the
socket 350 and tabs 352). A first set of teeth 358a project
laterally away from the central plate 356 in a first direction,
while a second set of teeth 358b project laterally away from the
central plate 356 in a second direction. The first and second sets
of teach 358a, 358b extend from opposite ends of the central plate
356, and the first and second directions are generally opposite
each other. The sets of teeth 358a, 358b are each securely held to
the central plate 356 by two outer frames 360 which extend around
the periphery of the teeth 358a, 358b.
[0057] Accordingly, and as best seen in FIG. 28, the medical device
340 includes first and second grasping jaws 344, 346 each having a
proximal end 366 and gear teeth 368 which have been bent to project
orthogonally away from a main body of the jaw 344. Accordingly, the
first set of teeth 358a receive the gear 368 of the second jaw 346,
while the second set of teeth 358b receive the gear 368 of the
first jaw 344. Notably, having the proximal ends 366 of the jaws
344, 346 bent laterally/orthogonally as shown allows a single pin
380 to be passed through the gears 368 and thus shared by both jaws
344, 346. Still further, and as shown in FIG. 29, the housing 342
may thus include only a single guide surface 382 formed by a single
slot on each lateral side of the housing 342 for receiving the ends
of the single pin 380. It can be seen that the first and second
jaws 344, 346 thereby share a single guide surface 382 (a jaw guide
surface) and guide slot, thus ensuring their coordinated operation
and smooth opening and closing.
[0058] As also shown in FIG. 29, a slot 357 is formed in the
central plate 356, and is aligned with the pin 380 and jaw guide
surface 382 to receive the pin 380 as the driver 348 moves
forwardly relative to the jaws 344, 346. As discussed above and
shown in FIG. 30, when the pin 380 (shared by proximal ends 366 and
gears 368 of the jaws 344, 346) has hit the distal end of the
single jaw guide surface 382, the driver 348 will continue moving
distally to cause the gears 368 to rotate via the rack/teeth 358a,
358b of the driver 348, thereby inducing rotation of the jaws 344,
346.
[0059] Turning to FIGS. 31-33, another embodiment of the medical
system 420 and medical device 440 are depicted. In this embodiment,
medical system 420 again includes a drive wire 422 having a distal
head 432 which is formed by bending the distal end of the drive
wire 422 into the shape shown. The medical system 420 also includes
a catheter attachment 430 which is generally a tubular member that
is connected to the distal end of the catheter 24 and is used to
slidably receive the connection block 426. The catheter attachment
430 includes a pair of openings 434 to provide access to the
control wire 422 and the connection block 426, whereby a tool may
be used to hold the connection block 426 in either a retracted or
extended position, as further described in copending U.S. Appln.
Nos. 61/391,878 and 61/391,875, the disclosures of which are hereby
incorporated by reference in their entirety.
[0060] The medical device 440 includes a housing 442 which is
detachably connected to the catheter 24 and its catheter attachment
430 via the connection block 426. The housing 442 slidably receives
the pair of jaws 444 which are connected to the drive wire 422 via
the driver 448. As with the previous embodiments, the driver 448
includes a socket 450 defined by locking tabs 452 which releasably
engage the distal head 432 of the drive wire 422. The distal
portion of the driver 448 includes a plurality of teeth 458 which
define a gear or rack which serves to drive rotation of the jaws
444 as previously described. The distal end 466 of the driver 448
includes a pocket defined by flanges which are used to fixably
engage the biasing strip 490. The housing 442 further defines a
pair of guiding surfaces or slots 482 which guide the longitudinal
and rotational movement of the jaws 444.
[0061] In this embodiment, the jaws 444 and housing 442 are
structured such that in the fully retracted position (shown), the
jaws 44 project (at least partially) out distally from the end of
the housing 442. As best seen in FIG. 32, as the distal head 432 is
pushed through the locking tabs 452 they are plastically deformed
outwardly to engage the shoulders 446 in the housing, and the jaws
444 are fully retracted. In this way, the length of the housing 442
can be shortened, as can the guiding slots 482 therein for guiding
the jaws 444. It can also be seen in FIG. 32 that the distal ends
of the jaws 444 include serrations 445 or other structures which
may aid in gripping tissue.
[0062] It is also noted that in this embodiment, as with all prior
embodiments, the drive wire 422 is capable of transmitting
rotational force and torque (e.g. from the proximal operating end
of the system 20/420) through the distal head 432 and the driver
448 to the jaws 444. As such the medical device 440 may be rotated
via rotation of the drive wire 422, i.e. the jaws 444, jaw pins
(e.g. 80), housing 442, and driver 448 all rotate as a unit
relative to the catheter 24. Inasmuch as the housing 442 may also
be non-rotatably connected to the connection block 426 (e.g.
depending on the friction therebetween), the connection block 426
may also rotate within the catheter attachment 430 (or the
catheter, e.g. 24) when the catheter attachment 430 is not used.
Accordingly, the orientation of the jaws 444 may be rotated through
rotation of the proximal end of the drive wire 422 to orient the
jaws relative to the tissue or material being grasped or clipped.
It has been found that forming the drive wire 422 out of a solid
nitinol wire has provided good torque transmission for rotation of
the medical device 440.
[0063] It has also been found that having the jaws 444 project at
least partially out of the housing 442 in their fully retracted
position allows the orientation of the jaws 444 to be visualized so
that it is easier to rotate the jaws 444 prior to opening and
closing them around tissue. Still further, additional tissue may be
encapsulated in the jaws 444 before the tissue abuts the distal end
of the housing 442. The distance which the jaws 444 project from
the housing 442 may be varied depending upon a particular
application, i.e. sized to correspond to the thickness of the
tissue or the type of procedure being formed to insure good spacing
between the distal ends of the jaws 444 and the distal end of the
housing 442.
[0064] Yet another embodiment of a driver 548 is shown in FIGS.
34-37, and a variation thereof in FIG. 38. The driver 548 again
generally includes a proximal portion 548p, a distal portion 548d,
and an intermediate portion 548i therebetween. The proximal portion
548p again defines a socket 550, here formed by a solid frame or
ring 551. The drive wire thus preferably includes a distal head
such as the hook 132 (FIGS. 20-21) or other shape than can fit
through the socket 550 and longitudinally engage the driver 548. As
with some of the prior embodiments, the distal portion 548d of the
driver 548 again includes a central spine 556 and opposing teeth
558 to form a rack that rotates the grasping jaws. The distal end
566 of the driver 548 includes a pocket 568 defined by two inwardly
projecting flanges 570 to engage an optional biasing strip, as
discussed above.
[0065] In this embodiment, the intermediate portion 548i of the
driver 548 is structured to be deformable, whereby locking legs 552
move laterally/radially outwardly to engage the housing 543 (FIG.
37) and lock the jaws to prevent them from sliding distally and
rotating open. As best seen in FIGS. 34 and 35, the intermediate
portion 548i includes a deformable frame 580 including a proximal
member 581, a distal member 582, and two opposing lateral members
583, 584, which together define an enclosed intermediate space 587
therebetween. The proximal member 581 is connected to the driver's
proximal portion 548p via a thin neck 590 directly connected to the
ring 551 of socket 550, discussed further herein. The distal member
582 is connected to the driver's distal portion 548d via the
central spin 556 as shown. The distal member 582 further includes
deformable areas 585, 586 at its lateral ends, which are structured
to deform and thus serve as living hinges. Preferably the frame 580
plastically deforms to permanently lock the clip.
[0066] The locking legs 552 are formed in the intermediate portion
548i at the locations where the lateral members 583, 584 meet the
distal member 582, and in particular the deformable areas 585, 586.
The locking legs 552, alone or in combination with the lateral and
distal members 582, 583, 584, define extensions 588, 589 of the
intermediate space 587, and generally have a V-shape or U-shape.
Stated another way, the intermediate space 587 has a general
C-shape in the normal operating condition shown in FIG. 34.
[0067] Upon application of a predetermined force differential
between the driver's proximal portion 548p and distal portion 548d,
the frame 580 deforms such that the locking legs move outwardly
away from the longitudinal axis LA, as shown by the arrows in FIG.
35. In particular, the longitudinal distance (denoted by D.sub.l in
FIG. 35) of the intermediate space increases (as does the overall
length of the driver 548), and the intermediate space changes from
its general C-shape to a generally rectangular shape. As best seen
in FIG. 35, the deformation of the frame 580 primarily occurs
within the deformable areas 585, 586 of the distal member 582,
however the lateral members 583, 584 and/or the locking legs 552
may also slightly deform when the driver 548 is stretched due to
the force differential. The force differential is generally caused
by the user placing a proximally directed force of the drive wire
while the grasping jaws are engaged with tissue (or other material)
and engaged with the distal end of the housing such that further
proximal withdrawal of the jaws is blocked.
[0068] Upon deformation of the frame 580 and rotation of the
locking legs 552 outwardly, further proximal force on the drive
wire will induce a second force differential between the driver's
proximal portion 548p and the intermediate portion 548i, whereupon
the neck 590 is designed to fail such that the drive wire (still
attached to proximal portion 548 via socket 550) can be moved
further proximally to detach the delivery catheter from the housing
of the clip, leaving the clip in place and locked on the tissue.
FIG. 37 shows an alternate housing 532, which includes a driver
guide surface 596. A proximal section 596p of the guide surface 596
is wider than the distal section 596d, thereby forming a shoulder
598 that can be engaged by the contact surfaces 553 of the locking
legs 552. The contact surfaces 553 have been shown as
frusto-conical in shape, but may be pointed or rectangular.
Similarly, the shoulder 598 is shaped to be engaged by the legs
552, and is orthogonal to the longitudinal axis LA, and may even be
sloped proximally (i.e. to the right on the page in FIG. 37).
Multiple shoulders 598 may also be formed to create a one-way
ratcheting mechanism.
[0069] A variation of the driver 548 described above is shown in
FIG. 38. This driver 648 includes a distal portion 648d and an
intermediate portion 648i similar to those described above. In this
variation, the neck 690 is not designed to fail under a
predetermined load (force differential), but rather the proximal
portion 648p of the driver 648 is designed to release the drive
wire under a predetermined force. Here the outer ring 651 defining
the socket 650 includes a throat 649 that is deflectable and
provides the socket 650 with a proximally facing opening. At the
same time, the proximal portion 648p does not include the locking
tabs, but rather the intermediate portion 648i again defines
locking legs 652 which operate as described above with reference to
legs 552.
[0070] The foregoing description of various embodiments of the
invention has been presented for purposes of illustration and
description. It is not intended to be exhaustive or to limit the
invention to the precise embodiments disclosed. Numerous
modifications or variations are possible in light of the above
teachings. The embodiments discussed were chosen and described to
provide the best illustration of the principles of the invention
and its practical application to thereby enable one of ordinary
skill in the art to utilize the invention in various embodiments
and with various modifications as are suited to the particular use
contemplated. All such modifications and variations are within the
scope of the invention as determined by the appended claims when
interpreted in accordance with the breadth to which they are
fairly, legally, and equitably entitled.
* * * * *